Flex Duct Between Floors

Attic installations attic installations lend themselves readily to all of the duct system types.

Flex duct between floors.

Add a false return grille cut an access hole in the ceiling of the first floor in a central area to gain access to the ducts. Also make sure to use hvac tape and seal all of the joints between duct segments. No air should be able to penetrate the ductwork and the joints are a natural weak point. Sometimes the best route for a flexible duct run is up and over an obstruction.

The supports need to be at the manufacturer s recommended spacing but no longer than 4 maximum. The insulation you use to wrap your ducts should leave no gaps and be at least two inches thick to work effectively at reducing or eliminating condensation on ductwork. The official recommendation from the adc is that flex ducts should sag no more than 1 2 per foot of length between supports. This size fits just between most floor joists.

A duct system located in an attic must be insulated and must have a vapor barrier. Without it there would be tons more labor and material to make that final connection. Flexible duct performance in. Another biggie that i see all the time is sagging ducts.

If no data is available use the generic flexible duct friction loss chart in acca manual d. Hart cooley offers flexible duct products for both residential and commercial applications that provide the most economical solution to your air handling needs. Here are several ways to access ducts. But without proper support ducts can develops sags or kinks that reduce airflow 4a 4b.

Keep flex ducts as short as possible between the hard duct and the hvac grille. Between floors of multistory structures crawl space installations conditioned space installations embedded in concrete slab. The straps that hold up the flex duct need to be no less than 1 5. Use the minimum length of flexible duct needed to make the connections.

The most common size duct used is 14 in. Flex duct allows easy connection from the main duct trunk to the hvac grille. To prevent problems use saddles or straps to support at regular intervals 4c 4d follow the manufacturer s instructions but in case they get lost here is a list of best practices for. Since all flexible ducts are not alike use the flexible duct manufacturer s air friction loss data to size the ducts whenever possible.